783620H / 1013 10. JOB FILES
ASK_SPECTRUM
LOOP 5
SAVE “$(FULLBASE)$(LOOP1).$(FILEEXT)”
END_LOOP
10.3. JOB Programming Example
A common operation that is ideal for a
.JOB
file is the collection of many consecutive sample spectra without user intervention. An example of this is the collection of a series of spectra to show the radioactive decay in a particular sample.
This process can be described as follows:
1) Set the Detector parameters, such as live time.
2) Start the acquisition.
3) Wait for the acquisition to stop.
4) Integrate the nuclide peak.
5) Record the peak area.
6) Repeat this for the required number of samples.
By looking at the list of steps above and the explanations below, the necessary commands can be determined and written down.
The first step in the process is to initialize the Detector to the condition needed of 1000 seconds live time. These are:
SET_DETECTOR 1
SET_PRESET_CLEAR
SET_PRESET_LIVE 1000
CLEAR
Note that all the presets were cleared before setting the live-time preset. This is to ensure that no previous presets (left over from other users) will interfere with this analysis.
Now start the acquisition and wait for completion of the live time.
START
WAIT
During this time the display manipulation keys are active so that the spectrum can be studied while collection is taking place.
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Now move the spectrum from the Detector to the buffer. Select the buffer for the computational step.
FILL_BUFFER
SET_DETECTOR 0
In this step, the nuclide peak of interest is being marked by reading in an
.ROI
file. This
.ROI file has been previously defined by looking at the spectrum and marking the peak (or the region around the peak). This ROI data is saved on the disk under the name
DECAYPK.ROI
. This
.JOB
file will work on different peaks or nuclides just by changing the
.ROI
file.
RECALL_ROI “DECAYPK.ROI”
The peak areas of the marked peak or peaks is printed on the printer by this command.
REPORT “PRN”
This gives a list of the peak areas and count rates for the marked peak. If the library has a peak near this energy then the peak identity will also be printed.
The set of instructions, as written so far, will only collect and report once. There are two ways to make the process repeat itself for a series of samples. The first and hardest is to write one set of the above instructions for every sample in the series. A much more efficient way is to use the
LOOP command. To use this, put LOOP before CLEAR and END_LOOP after REPORT. The whole
.JOB
file now looks like this:
SET_DETECTOR 1
SET_PRESET_CLEAR
SET_PRESET_LIVE 1000
LOOP 10
CLEAR
START
WAIT
FILL_BUFFER
SET_DETECTOR 0
RECALL_ROI “DECAYPK.ROI”
REPORT “PRN”
SET_DETECTOR 1
END_LOOP
Note that an additional SET_DETECTOR 1 has been inserted after REPORT, so the loop will
operate on the desired Detector.
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